Major Projects

Hydro One's Current Transmission System Projects In Ontario.
photo of a transmission tower

The transmission system is Ontario’s electricity highway. Through it we send vast amounts of electricity from hydroelectric, wind, solar, nuclear, and natural gas generators over long distances to the Local Distribution Companies (LDCs) that power Ontario homes and businesses.

We continue to make investments to maintain and upgrade our system. We work with communities to ensure that our transmission system has sufficient capacity to deliver a safe and reliable supply of electricity.


Photo of Hydro One workers on a transmission tower

The Planning Process

Each major project is unique, but they all follow a similar planning process. Explore our integrated planning approach here.

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Chatham to Lakeshore Line

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Power Downtown Toronto

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Waasigan Transmission Line
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Lakeshore Transmission Stations
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Featured Projects:

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Power Downtown Toronto

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Lakeshore Transmission Stations Project

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Chatham to Lakeshore Line

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Image of the Waasigan Transmission Line Project logo

Waasigan Transmission Line

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Photo of a Hydro One transmission station during a rain storm with a double rainbow behind it

Class EA for Minor Transmission Facilities

Some transmission system projects require a Class Environmental Assessment (EA) before they can proceed.

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